Category Archives: Plants & Fungi

plants & fungi

A Thornless Rose? There’s a Gene For It

Thorns (actually prickles) on a rose (photo from Wikimedia Commons)

21 October 2024

Thornless roses are the rose fancier’s dream but are difficult to breed, are usually infertile, and require a genetic mutation to block the prickles from emerging on the skin. Because the underlying trigger is still present, new growth on a “thornless” rose can produce prickles at the drop of a hat — injury, root suckers, etc.

What we call “thorns” on roses are technically prickles because they grow out of the skin. Roses, wineberry and devil’s walking stick have the same gene coding for prickles.

Wineberry prickles, Schenley Park, Nov 2019 (photo by Kate St. John)
Devil’s walking stick (or maybe Japanese angelica), Jan 2021 (photo by Kate St. John)

What are the genes underlying prickle development? Two studies published in August 2024 investigated Solanum prickle plants (eggplants, tomatoes) and found that they share the same LOG family genes. When scientists disrupted those genes it resulted in prickle loss in multiple species and did not adversely affect other parts of the plant.

Because roses have prickles and may share the same gene coding, there is new hope for creating a truly smooth stemmed rose.

See a summary of the studies in Smithsonian magazine. The two scientific studies are here and here.

p.s. Why are rose thorns actually prickles? Find out at Ohio State University: Armed by Nature: Thorns, Spines, and Prickles

Fungi Remember and They Have a Plan

Fruiting body of split gill mushroom, College Station, TX (photo from Wikimedia Commons)

20 October 2024

This week the Good News Network reported on a study published in ScienceDirect that shows fungi perceive shapes in the world around them, have memories, make decisions and solve problems. All without a brain!

A Japanese study of fungal networks set up an experiment with wood cubes pre-colonized with a wood decaying fungus, Phanerochaete velutina. The fruiting body and mycelia are shown below.

Fruiting bodies and mycelia of wood decay fungus, Phanerochaete velutina (photo by Gerald Holmes, Strawberry Center, Cal Poly San Luis Obispo, via Bugwood.org)

The scientists laid the cubes on a bed of clean soil in two patterns, a circle and an X, then observed and photographed what happened over a period of months.

  • By Day 13 the fungi had grown filaments (hypha) that made the cubes look fuzzy, particularly in the X shape. (hypha are collectively called mycelia)
  • By Day 34 some filaments from each cube had joined with the mycelia of neighboring cubes, but the rest of the hyphae were still seeking so the shapes were super fuzzy.
  • By Day 116, almost four months later, the “chatter” had subsided and the fuzzies were mostly gone in favor of strong, efficient networks.

Over time it became obvious that the fungi were not acting randomly. They remembered shapes and were making decisions.

If the fungi didn’t display decision-making skills, they would simply spread out from a central point without consideration for the position of the blocks.

For the X arrangement, the degree of mycelial colonization was greater in the outermost four blocks. It was hypothesized that this was because the outermost blocks can serve as “outposts” for the mycelial network to embark on foraging expeditions, therefore more dense connections were required compared to the five blocks inside the X.

In the circle arrangement, the degree of mycelial colonization was the same at any given block. However, all the empty space inside the circle remained clear. It was proposed that the mycelial network did not see a benefit in overextending itself in an already well-populated area.

Good News Network: Scientist Shows Fungi Are ‘Mind-blowing’: They Have Memories, Learn Shapes, Can Make Decisions and Solve Problems

In order to optimize their patterns the fungi must be communicating through the network. That’s where the beautiful split gill mushroom (Schizophyllum commune), shown at top, comes in.

Two years ago a study of electrical signals in the filaments (hypha) of enoki, split gill, ghost and caterpillar fungi discovered that their signals pulse when there’s something important to say such as “Found a new source of food.” Sometimes the pulses were similar to words and it appeared that the fungi knew 50 “words.”(*)

Read more about the “word” study at Good News Network: Research Suggests Mushrooms Talk to Each Other With a Vocabulary of 50 ‘Words’(*) See the source publication at Royal Society of Open Science: Language of fungi derived from their electrical spiking activity.

(*)NOTE: Some skepticism was reported at the end of the Good News Network “words” article:

Some scientists are skeptical that the research was done looking for ‘language’, suggesting that this puts a shroud of exaggeration and overexcitement about the findings.

To his credit, Adamatzky explained to the Guardian that it could be simply that the electrically-charged tips of hyphae were just creating electromagnetic reactions as they explore the forest underground.

Research Suggests Mushrooms Talk to Each Other With a Vocabulary of 50 ‘Words’

Seen This Week

Insect on New York aster, Toms Run, 16 Oct 2024 (photo by Kate St. John)

19 October 2024

This week brought:

  • Fall colors and the first piles of fallen leaves
  • Late flowers and insects
  • “See Your Breath” cold mornings
  • The first juncos … and …
  • Several thousand crows in Oakland.

In photos, late asters attracted an insect at Toms Run and morning sun slanted through the trees in Schenley Park.

Fall colors and fallen leaves, Schenley Park, 18 Oct 2024 (photo by Kate St. John)

Many trees are changing color. The oaks aren’t there yet but they have dropped their acorns leaving empty acorn cups on the branches. It’s a big mast year for red oaks in Pittsburgh.

Red oak leaves and acorn cups, 13 October 2024 (photo by Kate St. John)

A rhododendron in Shadyside is confused. Is it spring?

Confused rhododendron blooming in Pittsburgh, 13 Oct 2024 (photo by Kate St. John)

This week crows were absent from Oakland during the day but arrived in huge flocks at dusk, staging on rooftops before flying to the roost. I fumbled to photograph them on the RAND Building last Sunday. This is only a fraction of the flock that flew away.

Crows make a stop on the RAND building before sunset, 13 Oct 2024 (photo by Kate St. John)

Obviously they’ve been roosting on Pitt’s campus. I found evidence below trees at the Pitt Panther statue. The Crows Slept Here Last Night.

Evidence at Pitt that The Crows Slept Here Last Night, 17 October 2024 (photo by Kate St. John)

Mangroves Protecting The Coast

Great egret among mangroves in Gambia (photo from Wikimedia Commons)

18 October 2024

I have heard that mangroves protect coastlines during hurricanes and tsunamis but I could not imagine how they did it until I saw this video from Licypriya Kangujam (@LicypriyaK), Special Envoy for the President of the Republic of Timor-Leste and 13 year old climate activist.

Timor-Leste, also known as East Timor, is the eastern half of Timor island, located north of Australia. The other half of the island is part of Indonesia.

Map of Timor Leste from Wikimedia Commons

Timor was created by volcanoes so its mountains are steep and nearly everyone lives on the coast. It is good to live by the sea, but they need mangroves to protect them.

Scene from East Timor (photo from Wikimedia Commons)

Timor island is located in the region with the highest diversity of mangroves in the world — 26-47 species in one place. Compare this to just one or two species in Louisiana.

Map of mangrove species distribution worldwide (from ResearchGate: Oil Spills in Mangroves: Planning and Response)

When a hurricane hits Louisiana we often hear that the damage would not have been so great if they had more mangroves. Louisiana is now trying to restore their mangrove forest but it slow going.

Learn more about mangroves in this award-winning video from The Marine Diaries.

video embedded from The Marine Diaries on YouTube

A Tomato That Thrives in Salty Soil

Currant Tomato (Solanum pimpinellifolium) at Pantanos de Villa, Chorrillos, Peru (photo by ruthgo via iNaturalist)

15 October 2024

Many crops around the world are irrigated but this inevitably leads to salty soil. Eventually the land becomes useless for agriculture.

Irrigation eventually makes the soil salty: Irrigation rig in Yuma County, AZ, 1987 (photo from Wikimedia Commons)

USDA explains:

What happens when you irrigate?
Irrigation inevitably leads to the salinization of soils and waters. In the United States yield reductions due to salinity occur on an estimated 30% of all irrigated land. World wide, crop production is limited by the effects of salinity on about 50% of the irrigated land area. … Concern is mounting about the sustainability of irrigated agriculture.

Where does all the salt come from?
Application of irrigation water results in the addition of soluble salts such as sodium, calcium, magnesium, potassium, sulfate, and chloride dissolved from geologic materials with which the waters have been in contact. Evaporation and transpiration (plant uptake) of irrigation water eventually cause excessive amounts of salts to accumulate in soils unless adequate leaching and drainage are provided.

USDA Agricultural Water Efficiency and Salinity Research Unit: Riverside, CA: Frequently Asked Questions About Salinity

Salt residue makes the soil hostile for everything, even weeds.

Salty residue after irrigation water percolated up and evaporated, 2011 (photo from Wikimedia Commons)

This worldwide problem will get only worse as climate change increases drought, so a team of researchers looked for salt tolerant crops.

Focusing on the tomato’s closest wild relative, the tiny currant tomato (Solanum pimpinellifolium), they selected “over 2,700 cultivars, raising the seedlings in two environments: a greenhouse, and an open field.”

The best results came from five cultivars from Peru.

Currant tomato flowers in Lambayeque, Peru(photo by jackychj via iNaturalist)
Currant Tomato (Solanum pimpinellifolium) at Los Pantanos de Villa near Lima, Peru

What genes do these plants have that make them thrive? That’s a question for the next study.

Read more in Anthropocene Magazine: A tiny tomato may harbor the secret to salt-tolerance in a climate-changed world. “The closest living wild relative of the common tomato holds untapped genetic secrets thanks to its large diversity.”

Seen This Week

Sun rays through the mist, Schenley Park, 4 Oct 2024 (photo by Kate St. John)

12 October 2024

This week’s biggest Seen event was the aurora borealis which I wrote about yesterday (Northern Lights Last Night in Pittsburgh), but there were also subtle changes in the landscape that prompted a few photos.

Cold weather brought foggy mornings and sun rays burning through the mist in Schenley Park, at top.

It’s a big mast year for Schenley’s red oaks. These shallow, tightly scaled cups are the easiest way to identify red oak versus white oak.

Closeup of two red oak acorns with caps, 8 Oct 2024 (photo by Kate St. John)

It was hard to find two acorns that still had their cups. These two are intact because a worm drilled into the nuts. I searched through lots of cup-less acorns to find them.

Big mast year for red oaks in Schenley Park, 8 Oct 2024 (photo by Kate St. John)

For decades I’ve walked past these trees without thinking about their odd looking trunks. The trunks have hips because …

Grafted cherry trees, Schenley Park near Westinghouse Memorial, 8 October 2024 (photo by Kate St. John)

… these ornamental cherry trees were grafted onto healthy trunks of (probably) native trees. This is usually done because the non-native tree roots are likely to fail in North America.

Grafted cherry trunk, Schenley Park, 8 October 2024 (photo by Kate St. John)

Fall leaf color is not brilliant yet but burning bush berries are ready to entice birds. Euonymus alatus is a pretty plant but is officially a Noxious Weed in Pennsylvania since January 2023.

Euonymus fruit in garden bed, 2 Oct 2024 (photo by Kate St. John)

Let Your Garden Sleep In

Monarch butterfly on salvia (photo from Wikimedia Commons)

3 October 2024

On Tuesday I saw a monarch butterfly fly past my 6th floor window on its journey south. Every night that butterfly it will rest in sheltering vegetation and feed on flowers the next day. But what if those amenities aren’t available?

On Wednesday I noticed landscaping staff clearing a garden in front of an Oakland office building. Monthly gardening schedules, sometimes based on pre-climate change temperatures, call for clearing the garden or changing the plants in October. Salvia looks “leggy” now. Perhaps they were going to plant chrysanthemums.

Fortunately Saving Monarchs sends this helpful Facebook reminder for all gardeners. Take a break and let your garden sleep in!

This is a tiny screenshot. Click here to see the full Saving Monarchs post on Facebook!(*)

About the sign, Saving Monarchs says:

Some have messaged me asking if they can buy the sign, yes, they’re available for purchase. The large aluminum signs measure 18”x 12” are 50 plus shipping. I also make them in pvc size 9” x 11.5” and are 25 plus shipping. No extra shipping if you purchase more than 1. Obviously, due to shipping costs no posts are included, just the signs. Message [Saving Monarchs on Facebook] if you’re interested.

Read more about the benefits of leaving the leaves for insects, pollinators, birds, and even salamanders.

(*) p.s. I used a screenshot of the Saving Monarchs sign because Facebook’s embedded posts do not display on mobile devices.

Refueling on Migration

Cape May warbler on Devil’s Walking Stick look-alike: Japanese angelica, 6 Sept 2023 (photo by Dave Brooke)

19 September 2024

During my recent journey in southern Spain I appreciated the opportunity to rest and refuel.

This month warblers are making their own long journey at night to Central and South America. When convenient they stop during the day in Pennsylvania to refuel on the fruit in our parks and gardens and on the insects that crawl on the fruit.

Seven years ago I wrote about what attracts them to stopover in our city parks. This vintage article is updated to reflect the real name of their favorite fruit in Frick Park.

More Weeds That Deer Don’t Eat

Sweet wormwood (Artemisia annua) in Schenley Park, 30 August 2024 (photo by Kate St. John)

4 September 2024

Last weekend I noticed this group of tall plants in Schenley Park with a distinctly Christmas tree shape, shown above. They are not beautiful, they are certainly weeds, and they are thriving in a place where deer have eaten all the non-poisonous native plants. These are either poisonous or unpalatable.

I took a closeup of the leaves and asked Picture This to identify it: Sweet wormwood (Artemisia annua), native to temperate Asia.

Sweet wormwood (Artemisia annua) in Schenley Park, 25 Aug 2024 (photo by Kate St. John)

Plants in the Artemisia genus taste bitter and their crushed foliage and stems have a strong smell. Deer find it extremely unpalatable and can tell from far away that it smells too ugly to approach.

Deer in Frick Park, 17 Aug 2024 (photo by Kate St. John)

Plants in the Artemisia genus often have medicinal properties. Sweet wormwood (A. annua) contains artemisinin which was discovered in 1972 and is used to treat malaria. Unfortunately the malarial parasite in Southeast Asia has developed artemisinin resistance so the drug can no longer be used alone to cure the disease.

Sweet wormwood’s close relative common mugwort (Artemisia vulgaris) also has a wide range of supposed pharmacological uses. These uses probably account for the plant’s presence in North America. The Pittsburgh area has plenty of it!

Mugwort (Artemisia vulgaris) at the Hays Eagle Watch site, June 2017 (photo by Kate St. John)

Another reason why sweet wormwood, in particular, may be thriving this year is that mature plants are fairly drought resistant — and we are in a drought.

U.S. Drought Monitor map from UNL, 2024-08-27

Drought and deer this summer have combined to leave Pittsburgh with so many weeds.

Yesterday in Schenley Park

Schenley Park outing participants, 25 August 2024 (photo by Kate St. John)

26 August 2024

Yesterday morning 13 of us found 24 species of birds in Schenley Park plus flowering plants and insects.

Best Birds were the six+ ruby-throated hummingbirds (Archilochus colubris) sipping nectar at orange jewelweed (Impatiens capensis) along Phipps Run and at Panther Hollow Lake. Between sips they chased each other everywhere.

Orange jewelweed, favorite of hummingbirds, Schenley Park, 25 Aug 2024 (photo by Kate St. John)

So many hummingbirds was a happy sign after 7-8 years without big numbers in Schenley Park. Orange jewelweed is their favorite food on migration but it was eradicated 7-8 years ago by Schenley’s overabundant deer population. This year jewelweed patches thrive in inaccessible places at Phipps Run and among the cattails in Panther Hollow Lake. If you want to see hummingbirds, pause here and watch the jewelweed. Also check the wires above the lake.

Best insects were several red spotted purple butterflies flitting on the Lake Trail. Hailey Latona found one resting … but not for long. (Bug people: If I’ve misidentified this butterfly please correct me!)

Red spotted purple butterfly in Schenley Park, 25 Aug 2024 (video by Hailey Latona)

We also found a Honeybee Heaven near the railroad tracks. I had never noticed Japanese hop (Humulus japonicus) growing there but yesterday I could hear the flowers humming and saw it swarming with honeybees.

A species of hops at Schenley Park. Is it Japanese hops? 25 Aug 2024 (photo by Kate St. John)

By 10:30am it was getting hot but we found a chestnut-sided warbler so we paused to look harder. Alas, it was the only warbler species for the outing. Here’s our checklist.

Schenley Park, Allegheny, Pennsylvania, US Aug 25, 2024 8:30 AM – 11:00 AM

Canada Goose (Branta canadensis) X Maybe 40 on Flagstaff Hill; evidence at Panther Hollow lake
Mourning Dove (Zenaida macroura) 4
Chimney Swift (Chaetura pelagica) 2
Ruby-throated Hummingbird (Archilochus colubris) 6 — Lots of chasing
Downy Woodpecker (Dryobates pubescens) 2
Northern Flicker (Colaptes auratus) 2
Eastern Wood-Pewee (Contopus virens) 3 Heard
Red-eyed Vireo (Vireo olivaceus) 5
Blue Jay (Cyanocitta cristata) 6
Carolina Chickadee (Poecile carolinensis) 4
Tufted Titmouse (Baeolophus bicolor) 1 Heard
White-breasted Nuthatch (Sitta carolinensis) 2
Carolina Wren (Thryothorus ludovicianus) 4
Gray Catbird (Dumetella carolinensis) 3
Wood Thrush (Hylocichla mustelina) 1 Seen
American Robin (Turdus migratorius) 4
Cedar Waxwing (Bombycilla cedrorum) 9
House Finch (Haemorhous mexicanus) 4
American Goldfinch (Spinus tristis) 10
Song Sparrow (Melospiza melodia) 8
Baltimore Oriole (Icterus galbula) 2
Red-winged Blackbird (Agelaius phoeniceus) 3
Chestnut-sided Warbler (Setophaga pensylvanica) 2
Northern Cardinal (Cardinalis cardinalis) 2

View this checklist online at https://ebird.org/checklist/S192748114